What happens to authoritarian ruling parties when they accept democracy and reinvent their organizations, symbols, and programs to comply with the norms of free political competition? The consequences of such reinvention have been neglected empirically, yet they are critical for our understanding both of the costs and benefits of party transformation and for the health of democratic party competition. Using a novel data set comprising 81 countries over 1945–2015, and a structured comparison of two prominent cases of authoritarian reinvention, this article makes three contributions. First, it distinguishes among the different strategies available to authoritarian ruling parties after the collapse of their monopoly regimes, including exit, dissolution, and reinvention. Second, it finds that the cruel paradox is that the biggest boosters and builders of party democracy—the reinvented authoritarian successor parties—eventually suffer the most electorally. Third, this paradoxical fate follows from their initial decisions to reinvent and transform themselves